Decimal tabulation mechanism



2 Sheets-Sheet 11 INVENTORS RONALD D. DODGE NEIL O. WALTON EM 6. Q1417, ATTORNEY Nov. 1, 1960 R. D. DODGE ETAL DECIMAL TABULATION MECHANISM Filed Dec. 23, 1958 FIG. 1

Nov. 1, 1960 R. D. DODGE ETAL 2,958,409

DECIMAL TABULATION MECHANISM Filed Dec. 23, 1958 2 Sheets-Sheet 2 United States Patent 2,958,409 DECIMAL TABULATION MECHANISM Ronald D. Dodge and Neil D. Walton, Lexington, Ky.,

assignors to International Business Machines Corporation, New York, N.Y., a corporation of New York Filed Dec. 23, 1958, Ser. No. 782,594 8Claims. (Cl. 197-178) This invention relates to decimal tabulation devices for typewriters, and more particularly to devices for stopping a typewriter carriage at any one of a plurality of decimal positions with a decelerating action.

In the typing of numerical information, it is desirable that means be provided for positioning the carriage to permit the typing of a digit in any denominational order of a multi-digit number. When typing a column of numbers, a decimal tabulation mechanism makes it possible to tabulate directly to the first significant digit in each number, thereby permitting the typing of numbers so that digits in corresponding order positions are in vertical alignment with each other. By providing decelerating means which operates to bring the carriage to a stop gradually regardless of the position to which it tabulates, shock and noise resulting from the operation of the machine is greatly reduced.

An object of this invention is to provide an improved decimal tabulation mechanism for a typewriter.

Another object is to provide an improved mechanism for tabulating a typewriter carriage to a position for typing a digit in any order position of a multi-digit number and bringing the carriage to a stop in such position without shock.

Still another object is to provide a decimal tabulation mechanism having a plurality of stops which may be moved selectively to positions for effecting the stopping of a typewriter carriage in a position corresponding to that of the stop actuated, and causing the stopping of the carriage in each position with a decelerated action.

Yet another object is to provide a mechanism for stopping a typewriter carriage in any one of different decimal positions by actuating keys corresponding to such positions, and providing an interlock which is operable to prevent the actuation of a key until the carriage has been stopped in a position corresponding to a previously actuated key.

Other objects of the invention will be pointed out in the following description and claims and illustrated in the accompanying drawings, which disclose, by way of example, the principle of the invention and the best mode, which has been contemplated, of applying that principle.

In the drawings:

Fig. 1 is a perspective View looking from the front of a typewriter and showing decimal tabulation stops adapted to be positioned in response to the manual actuation of keys. 7

Fig. 2 is a perspective view looking from the rear of the typewriter and showing a pivotally mounted frame supporting the decimal tabulation stops and connected to a deceleration mechanism.

This invention comprises generally, as shown in Fig. 1, a frame 1 having notches 2 in which counter stops 3 are selectively movable vertically to a position for engagement by a set tab stop or column stop 4 carried by a bar fixed to a typewriter carriage, not shown. The tab stop 4 is one of many which may be set by the operator in a position to engage any one of the counter stops moved to an elevated position. When typing a column of figures, the tab stop set is the one which eifects a stopping of the carriage in positions corresponding to the decimal tab keys actuated for typing the column of figures in the area desired on a sheet of paper.

Each of the counter stops 3 is provided with a notch 6 receiving a flange 7 on a member 8 forming part of the frame 1. The stop is normally held in a position with the flange adjacent the upper edge of the notch, and movement of the stop upwardly is limited by engagement of the lower edge of the notch with the flange. Extending through slots 10 in the member 8 are inter po-sers 11 having end portions which fit snugly within notches 12 in the stops 3. Each of the interposers is urged upwardly and forwardly by a spring 14 connected to a stationary part of the mechanism, not shown. The lower end of each interposer 11 is provided with a forwardly projecting portion 15 which extends under a stationary latch member 16 so that the interposer is held in the position shown. When the lower end of the interposer 11 is moved rearwardly to withdraw its portion 15 from under the member 16, the spring '14 lifts the interposer until the lower edge of the notch 6 engages the flange 7.

For moving the interposer 11 rearwardly, there is provided a lever 18 pivotally supported at 19 and engageable with a downwardly projecting portion 20 on the interposer. A spring 21 normally holds the lever 18 free of the projecting portion 20. Connected to the lower end of the lever is a Wire 23 slidably contained within a flexible tube 24 which is held stationary at its opposite ends by suitable means not shown. The wire is attached at its opposite end to a bellcrank 25 pivotally supported at 26 and urged in a clockwise direction by a spring 28. Mounted upon the bellcrank as shown, is a decimal tabulation key 30 adapted to be depressed by the operator of the machine. As indicated by Fig. l, the decimal tabulation key shown controls the stop 3 which effects a stopping of the carriage in a position for typing a digit in the tens of thousands (10T) order position. Other mechanisms like that described are provided for controlling other stops 3 at opposite sides of the one shown. The next decimal tabulation key to the right controls the stop for the next lower order position, and this stop is slidably mounted in the notches 2 just to the left of the stop 3 shown in Fig. 1. The stops for higher order positions are at the right side of the stop 3 in Fig. 1, and the decimal tabulation keys for these stops are at the left of the key 30.

Arranged adjacent the decimal tabulation keys 30 is a plate 32 pivotally supported at 33 and. having finger portions 34, each portion extending under a shoulder 35 formed on a stem 36 supporting the key 30. A depression of any one of the keys 30 causes the plate 32 to rock about its pivot 33, and the distance through which the key may be depressed is limited by a stationary plate 38 arranged in a position to be engaged by a shoulder 39 on the key stern. At the left end of the plate 32 is a cam assembly including a frame 41 pivotally supported at 42 and carrying a rotatable cam 43 which is engageable with a power roll 44. A spring 46 tends to rotate the cam into engagement with the power roll, but a lever 47 is normally in a position to latch the cam against such rotation. The plate 32 is connected by a link 48 to the lever 47 and operates to rock the latter for releasing the cam 43 when the plate is swung downwardly about its pivot 33. Engagement of the cam with the power roll causes the frame 41 to swing about its pivot 42 for actuating mechanism which will be described later.

Pivotally connected to the frame of the typewriter adjacent its left, rear corner is a lever 50 which operatively engages at its upper end a tab lever 51 supported for pivotal movement in a horizontal plane by plate members 52, 53. Extending downwardly from the tab lever is an arm 54 having a hook portion 56 engageable with a dog 57 which cooperates with an escapement rack 58 fixed t by suitable means, not shown, to the typewriter carriage This is a conventional tabulating mechanism and needs no further description. When the dog is moved out of engagement with the escapement rack, the carriage moves from right to left in Fig. 1 under the action of means which will be described shortly. The lever 50 is connected by a link 60 to the frame 41 of the cam assembly as shown in Fig. 1. When the cam 43 is driven by the power roll, the frame 41 operates to pull the link 60 forwardly and rock the tab lever in a direction to disengage the dog 57 from the escapement rack.

Referring to Fig. 2, it will be noted that the tab lever 51 carries at its rear side two bolts 62 which extend through elongated slots 63 in a plate member 64. When the tab lever is in its normal position, the left end of the plate member engages a stationary arm 65 and is held by the latter in a position with the bolts 62 at the left ends of the slots 63. A link 66 is loosely connected at one end to the member 64 by a pin 67, and is similarly connected at its other end to the frame 1 by a pin 68. As shown in Fig. 2, the frame 1 is pivotally connected to the upper ends of vertical members 70, 71 which are pivotally attached at their lower ends to the typewriter frame by means not shown.

When the cam 43 is driven by the power roll to rock the lever 50, the tab lever 51 is swung in a counterclockwise direction looking downwardly in Fig. 2. This causes the member '64 to move out of alignment with the arm 65 so the frame 1 may move to the left until the bolts 62 engage the right ends of the slots 63. It will be appreciated that the carriage moves from left to right in Fig. 2 since the view is taken from the rear of the typewriter. If one of the counter stops 3 is in its raised position and one of the tab stops 4 has been set, the movement of the carriage will eventually engage the stop 4 with the raised stop 3 and cause the frame 1 to move to the right until the member 64 is stopped by its engagement with the bolts 6'2 at the left ends of the slots 63. Just before the member 64 is stopped during such movement, its left end passes beyond the end of the arm 65 and the tab lever 51 is rocked in a clockwise direction by a spring 74, bringing the member 64 in alignment again with the arm 65.

For regulating the speed of the carriage during tabulation, and decelerating its movement just before it is brought to rest, there is provided a mechanism, generally designated 76, like that shown and described in the Dodge et a1. Patent 2,854,124. This mechanism comprises a reel 77 about which a tape 78 is wrapped. The tape passes from the reel around an idler pulley 79 and is connected at its opposite end to the typewriter carriage. Connected to the reel is a helical spring 80 which tends to rotate the reel in a direction to wind up the tape. A spring clutch, not shown, connects the reel to a gear 81 which meshes with a gear 82 connected to a centrifugal governor 83. As the reel is driven by the spring 80, the governor 83 operates to produce a braking action for limiting the speed of the carriage. Connected to the stop frame 1 through the pin 68 is a link 85 which is connected at its opposite end to a bell-crank 86. Carried by the bellcrank 86 is a roller 87 engaging a cam arm 88 which is supported for pivotal movement on an axis coincident with the axis of the gear 81. When the arm 88 tends to swing in a counter-clockwise direction at a speed greater than that of the gear 81, a spring clutch 90 operates to connect the arm to the gear. A spring 91 acts on the arm 88 to swing it in a clockwise direction and effect a rocking of the bellcrank 86 in a counter-clockwise direction.

When the tab lever 51 is actuated to move the member 64 out of line with the retainer arm 65, the bellcrank 86 is rocked counter-clockwise by the action of the spring 91 on the cam arm 88. This causes the frame 1 and the member 64 to move to the left until stopped by the bolts 62. The carriage then moves to the right in Fig. 2 under the control of the governor 83, and eventually the set tab is such that a rocking of the bellcrank 86 by movement of the frame 1. causes a turning of the cam arm at a speed greater than that of the gear 81 produced by movement of the carriage previous to engagement with the stop 3.

This causes the clutch spring to connect the arm 88.

to the gear 81 and drive the latter at an increased speed. The governor 83 operates to increase the braking force for slowing down the carriage still more during movement of the stop 3 to the right.

There is provided, as shown in Fig. 1, means for returning any one of the stops 3 from its raised position to the position shown upon movement of the frame 1 by engagement of the carriage with the stop. This means comprises a bail 93 pivotally supported at each end by a stud 94 engaging an arm 95 of a bellcrank 96 which rocks about a stud 97. A spring 98 is connected to the arm 95 and tends to rock the bellcrank in a clockwise direction against a stationary pin 99. Formed on the bail 93 is an upwardly extending flange 100 which is connected by a spring 101 to the bellcrank 96 for urging the bail to the position shown against a finger 104 on the arm 95. Extending upwardly from the lower end of the interposer 11 is a portion 106 lying just in front of the bail 93.

When the lower end of the interposer '11 is moved rearwardly, its portion 106 engages the bail 93 and rocks the latter about the studs 94 against the action of the spring 101. Soon after this, the bellcrank 96 is rocked in a counter-clockwise direction, moving the bail upwardly to a point where it is rocked by the spring 101 against the finger 104 and then overlies the portion 106. For rocking the bellcrank 96 in a counter-clockwise direction, there is provided a link 108 connecting the lower end of the crank to one end of a lever 109 which is pivotally supported between its ends by a pin 110 and is connected at its opposite end to the lower end of the cam frame 41 by a link 111.

Formed on the bellcrank 96 is a hooked arm 114 engageable with a latch 115 which is urged downwardly against the arm about a pivot point 116 under the action of a spring 117. A link 118 connects the latch to a bellcrank 120 pivotally supported at 121 and having an arm 122 engageable by a member 123 connected to the frame 1 as shown in Fig. 2. When the bellcrank 96 is rocked in a counter-clockwise direction, the latch 115 operates to hold it in a position with the bail 93 above the projecting portion 106 on the interposer 11. At this time, the frame 1 is moved to the left from the position in Fig. 2. As the carriage engages one of the stops 3 and moves the frame to the right, the arm 122 is engaged just before the movement of the frame is terminated. This causes the latch 115 to be raised, permitting the bellcrank 96 to swing forwardly and engage the bail 93 with the projecting portion 106 for moving any raised stop 3 to its lower position. When the interposer 11 has been moved almost to the lowest position to which it is movable, the spring 14 swings the bottom end of the bar forwardly to extend its portion 15 under the latch bar 16.

There is provided a mechanism which operates when the lower end of one of the interposers 11 is moved rearwardly, to lock the other interposers against such movement. This mechanism comprises, as shown in Fig. 1, a frame 125 pivotally supported at 126 and including two elongated members 127, 128 extending horizontally adjacent the rear sides of the interposers 11. There is sufiicient clearance between the interposers and the members 127, 128 to permit any one of the interposers to be moved rearwardly far enough to release it from the latch bar 16. Formed :on the back side of each interposer 11 is a projecting portion 130 having inclined surfaces 131, 132 at its upper and lower ends, respectively. This portion extends between the members 127, 128 when the interposer is moved rearwardly. As the interposer is raised by the spring 14, the surface 131 acts on the member 127 to swing the frame 125 until the member 123 is against the surfaces 132 on the inter posers in forward positions. With the parts in these positions, all of the interposers except the one raised are locked in their lower positions. When the raised interposer is moved downwardly again, its surface 132 acts on the member 128 to rock the frame 125 in a direction to release all of the interposers.

While there have been shown and described and pointed out the fundamental novel features of the invention as applied to a preferred embodiment, it will be understood that various omissions and substitutions and changes in the form and details of the device illustrated and in its operation may be made by those skilled in the art without departing from the spirit of the invention. It is the intention, therefore, to be limited only as indicated by the scope of the following claims.

What is claimed is:

1. In a typewriter having a movable carriage, a tabulating mechanism for said carriage comprising, in com bination, a tab stop mounted on said carriage, a plurality of counter stops movable selectively to positions for engagement by said tab stop to effect a stopping of the carriage, a frame slidably supporting said counter stops, means supporting said frame for movement in opposite directions within a plane parallel to the path of carriage movement, means for limiting the move ment of said frame in both directions, yieldable means urging said frame in a direction opposite to the direction of carriage movement during tabulation, means in cluding manually operable key levers for moving said counter stops selectively to positions for engagement by said tab stop, and a decelerating mechanism connected to said frame for opposing its movement by said tab stop engaging one of said counter stops, said decelerating mechanism producing an opposing force which varies with the rate of movement of said frame by said tab stop.

2. The mechanism of claim 1 including means nor mally retaining said frame in a position opposite that toward which it is urged by said yieldable means, releasable means for holding said carriage against tabulation, and means operable simultaneously with the movement of one of said counter stops [to stopping position for freeing said frame from said retaining means and releasing said carriage holding means.

3. The mechanism of claim 1 in which said means for moving said counter stops comprises an interposer operatively engaging each of said counter stops for movement therewith, a latch member engageable by said interposer for holding the latter against movement, means yieldably urging said interposer toward said latch member and in a direction to move the counter stop associated therewith, and means operating upon actuation of one of said key levers for releasing said interposer from said latch member.

4. In a typewriter having a movable carriage, a tabulating mechanism for said carriage comprising, in combination, a tab stop on said carriage, a plurality of counter stops movable selectively to set positions for engagement by said tab stop to arrest carriage movement, a frame slidably supporting said counter stops, means supporting said frame for movement in opposite directions within a plane parallel to the path of carriage movement, yieldable means urging said frame in a direction opposite to the direction of carriage movement during tabulation, an interposer connected to each of said counter stops for movement therewith, a latch member, each of said interposers being movable angularly relative to its associated counter stop into latching engagement with said latch member, means yieldingly acting on each of said interposers for urging it toward said latch member and in a direction to move its associated counter stop towards its set position, means including manually operable key levers for releasing said interposers selectively from said latch member, and decelerating means connected to said frame for opposing its movement by said tab stop engaging one of said counter stops.

5. The mechanism of claim 4 including a bail engageable with any one of said interposers released from said latch member, and means operable upon predetermined movement of said frame by engagement of said tap stop with one of said counter stops for actuating said bail to return a released interposer toward said latch member, said interposers being moved by said yielding means acting thereon, to latched positions free of said bail when said counter stops are returned from their set positions.

6. The mechanism of claim 4 including a bail associated with said interposers, means operable upon actuation of any one of said key levers for rocking said bail to an operative position, latching means for holding said bail in its operative position, a projecting portion on each of said interposers lying outside the path of said bail when in latching engagement. with said latch member, said projecting portion moving into the path of said bail upon release of one of said interposers from said latch member, and means for releasing said bail latching means upon predetermined movement of said frame by engagement of said tab stop with one of said counter stops.

7. In a typewriter having a movable carriage, a tabulating mechanism for said carriage comprising, in combination, a tab stop on said carriage, a plurality of counter stops movable selectively to set positions for engagement by said tab stop to arrest carriage movement, a frame slidably supporting said counter stops for movement to and from said set positions, means supporting said frame for movement in opposite directions within a plane parallel to the path of carriage movement, means for limiting the movement of said frame in said plane, yieldable means urging said frame in a direction opposite to the direction of carriage movement during tabulation, an interposer connected to each of said counter stops for movement therewith, a latch member, each of said interposers being movable angularly relative to its associated counter stop into latching engagement with said latch member, means yieldingly acting on each of said interposers for urging it toward said latch member and in a direction to move its associated counterstop toward its set position, means including manually operable key levers for releasing said interposers selectively from said latch member, means operable upon releasing one of said interposers from said latch member for locking all of the other interposers against release, and decelerating .means connected to said frame for opposing its movement by said tab stop engaging one of said counter stops.

8. The mechanism of claim 7 in which said interposer locking means comprises a locking frame having spaced elongated members extending transversely of said interposers at their sides opposite said latch member, a projecting portion on each of said interposers movable between said elongated members upon release from said latch member, means pivotally supporting said locking frame, and a cam surface on said projecting portion acting on one of said elongated members for pivoting said locking frame to move the other of said elongated members against the latched interposers to hold them against release.

References Cited in the file of this patent UNITED STATES PATENTS UNITED STATES PATENT OFFICE Certificate Patent No. 2,958,409 Patented November 1, 1960 Ronald D. Dodge and Neil D. Walton Application having been made jointly by Ronald D. Dodge and Neil D. lValton, the inventors named in the patent above identified, and International Business Machines Corporation, New York, N.Y., a corporation of New York, the assignee, and John H. Norcross of Poughkeepsie, N.Y., for the issuance of a certificate under the provisions of Title 35, Section 256 of the United States Code, adding the name of the said John H. N orcross to the patent as a joint inventor, and a showing and proof of facts satisfying the requirements of the said section having been submitted, it is this 6th day of February, 1962, certified that the name of the said J ohnH. Norcross is hereby added to the said patent as a joint inventor with the said Ronald D. Dodge and Neil D. Walton.

EDWIN L. REYNOLDS,

First Assistant Gammissz'oner 0 7 Patents. 

